| From | John Ogness <> | Subject | [PATCH printk v1 01/18] kdb: do not assume write() callback available | Date | Thu, 2 Mar 2023 21:02:01 +0106 |
| |
It is allowed for consoles to provide no write() callback. For example ttynull does this.
Check if a write() callback is available before using it.
Signed-off-by: John Ogness <john.ogness@linutronix.de> --- kernel/debug/kdb/kdb_io.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c index 5c7e9ba7cd6b..e9139dfc1f0a 100644 --- a/kernel/debug/kdb/kdb_io.c +++ b/kernel/debug/kdb/kdb_io.c @@ -576,6 +576,8 @@ static void kdb_msg_write(const char *msg, int msg_len) continue; if (c == dbg_io_ops->cons) continue; + if (!c->write) + continue; /* * Set oops_in_progress to encourage the console drivers to * disregard their internal spin locks: in the current calling -- 2.30.2
|